Originally posted by pentaxman If you look at the Mark Roberts site, you can see that the contacts on the lens are detected as 0 1 1 * 1 0 for F2.8 lenses and 0 0 1 * 1 0 for F4.0 lenses. It looks like the second contact from the left is not being detected and that is making the camera think it is an F4.0 lens instead of an F2.8 lens. The funny thing is that your mount looks to be coded 000*10 which would decode as an F4.5 to F32 lens.
That's not my mount, I found the image on the net and used it as an example of what my mount looks like. I did this to save time instead of photographing my lens, downsizing in Picasa and loading to ImageShack, which is my only system for web display and takes a lot of time. About as much time as I've spent explaining that the lens images I posted were not my lens.
Thanks Pentaxman. I will check out your very concise directions. I had F2.8 again for a little while then lost it, so your explanation of the pin losing contact seems quite possible.
Last edited by audiobomber; 10-08-2008 at 05:59 AM.